The British Ministry of Defence said on Tuesday that the UK would send a third warship, HMS Kent, to the Persian Gulf, adding, however, that the decision to do so is not related to the current row with Iran.
"These long-planned movements do not reflect an escalation in the UK posture in the region and are routine", the ministry stressed.
According to the officials, the HMS Kent, a Type 23 frigate, will deploy to the region later in the year in order to take over after the HMS Duncan.
Tensions between Iran and the UK escalated in July, when the Royal Navy and Gibraltarian authorities seized Iran's Grace 1 supertanker, claiming that it was smuggling 2.1m barrels of crude oil to Syria in violation of EU sanctions.
Later, London also stated that the Iranian Islamic Revolutionary Guard Corps had tried to "divert" a British Heritage tanker "from international to Iranian waters" in the Persian Gulf.
Iranian President Hassan Rouhani slammed London's decision to send a military escort with the tanker, stating that the UK's previous actions had endangered the safety of navigation in the region.